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Species loss and the structure and functioning of multitrophic
Species loss and the structure and functioning of multitrophic

... diversity. Second, even where food webs have a substantial component of basal species, these may be aggregated into broad groups (e.g. ‘periphyton’ or ‘phytoplankton’) rather than resolved to species. These problems make it difficult to judge whether difference in species richness among trophic leve ...
The short-term effect of sheep grazing on invertebrates
The short-term effect of sheep grazing on invertebrates

... incorporates taxonomic differences. As we use data on occurrence of species, we hereafter refer to this as taxonomic richness. Taxonomic levels considered were family, order, superorder, subclass, class, subphylum and phylum following a recent phylogenetic based taxonomy (Judd et al. 1999). In the c ...
Competitive avoidance not edaphic specialization drives vertical
Competitive avoidance not edaphic specialization drives vertical

... et al. (2011) found evidence that EM fungal community composition was strongly influenced by horizontal gradients in rooting density, with long- and short-distance exploration type species (sensu Agerer, 2001) being more common in areas of lower and higher root densities, respectively. Although it h ...
The vulnerability of provincially rare species (species-at
The vulnerability of provincially rare species (species-at

... changing climate is to identify the vulnerability of selected assets in a study area. We used NatureServe’s Climate Change Vulnerability Index (CCVI) on a subset of provincially rare species inhabiting the Lake Simcoe watershed, Ontario, Canada, to identify species that are potentially vulnerable to ...
Annual Reviews of Ecology, Evolution and Systematics
Annual Reviews of Ecology, Evolution and Systematics

... MacArthur et al. 1972). A large number of papers have examined this phenomenon (summarized by Faeth 1984, Wright 1980), and have sought to explain why in some cases aggregate densities were lower (density undercompensation) or higher (density overcompensation) on islands when compared with equivalen ...
ABSTRACTS - POPBIO is a conference
ABSTRACTS - POPBIO is a conference

... of naturalization success. given that many of the non-naturalized ornamental plants in Europe originate from warmer regions, they may have a head start under climate change. Using distribution modelling for almost 800 ornamental species, we have predicted the potential future invasion hotspots in Eu ...
ecosystem - UNL Entomology
ecosystem - UNL Entomology

... As a living organism on this planet, there is no escaping interaction. Whether its among the biological community, or with the physical environment itself; interaction defines an ecosystem. As British ecologist Arthur Tansley(1935) said, “Though the organisms may claim our primary interest, when we ...
Understanding the implications of climate change for woodland
Understanding the implications of climate change for woodland

... overwhelming pattern was for species bioclimatic space gains and mean figures for all species and  all scenarios to vary from 12% to 100% gain. These responses are primarily described in terms of  the change in climate space (i.e., the possible future distribution of a species governed solely by  cl ...
Extinction: bad genes or bad luck?
Extinction: bad genes or bad luck?

... problem by population biologists. Cases of extermination s f species by human activities are celebrated and well known: the extinction may occur directly by human predation (hunting, etc.) or indirectly through the effects of other species introduced by man. The existence of a fcw particularly spect ...
Vector Corruption - Department of Fisheries and Wildlife
Vector Corruption - Department of Fisheries and Wildlife

... the bullfrog to become established outside its native range. The species is a large, gape limited, i.e. the body size and width of the mouth determine how large a prey item it can consume, generalist carnivore, willing to cannibalize its own young. They are a highly adaptable species that can easily ...
A food web perspective on large herbivore community limitation
A food web perspective on large herbivore community limitation

... Here we develop a food web approach (i.e. a quantification of biomass consumption across species or trophic levels, hereafter referred to as consumption fluxes) to assess the relative importance of top-down and bottom-up processes in controlling ungulate populations in four species-rich African sava ...
The role of intra-specific trait variability in plankton biodiversity: a
The role of intra-specific trait variability in plankton biodiversity: a

... population level: abundance, growth rate, distribution - the processes that result in population dynamics occur at the individual level: feeding, motility, resource uptake, sex ...
FAQs On The Monarch Butterfly Endangered Species Act Petition
FAQs On The Monarch Butterfly Endangered Species Act Petition

... include the passenger pigeon and the Rocky Mountain grasshopper. The passenger pigeon went extinct in the early 20th century despite the fact that in the late 19th century it was one of the most abundant birds in the country, with flocks so numerous that by some accounts they darkened the sky for up ...
Progress
Progress

... declining group of insects, the butterflies. Butterflies, in many respects, make ideal indicator species, as they respond rapidly to changes in their habitat and its management. The project is totally dependent on the monitoring activities of volunteers, which are co-ordinated by Butterfly Conservat ...
FAQs On The Monarch Butterfly Endangered Species Act
FAQs On The Monarch Butterfly Endangered Species Act

... include the passenger pigeon and the Rocky Mountain grasshopper. The passenger pigeon went extinct in the early 20th century despite the fact that in the late 19th century it was one of the most abundant birds in the country, with flocks so numerous that by some accounts they darkened the sky for up ...
Network structure beyond food webs: mapping nontrophic and
Network structure beyond food webs: mapping nontrophic and

... trophic interactions can often be observed in the field, either directly or using simple methods such as the examination of gut contents. Second, unlike the binary nature of trophic interactions (e.g., a predator either eats the prey species or does not), the net outcome of most non-trophic interacti ...
Network structure beyond food webs: mapping non
Network structure beyond food webs: mapping non

... trophic interactions can often be observed in the field, either directly or using simple methods such as the examination of gut contents. Second, unlike the binary nature of trophic interactions (e.g., a predator either eats the prey species or does not), the net outcome of most non-trophic interacti ...
The ecological consequences of habitat fragmentation
The ecological consequences of habitat fragmentation

... All ecosystems are heterogeneous at some spatial scale. One of the greatest advances in theoretical ecology has been the realisation that spatial heterogeneity in environmental conditions can fundamentally alter the outcome of species interactions and community dynamics (Holt, 1984; Pickett & Cadena ...
30 years of the endangered species act
30 years of the endangered species act

... 200 to 300 Aleutian geese. Buldir was Many private landowners on the Califorone of few remaining islands with no nia coast and in the Sacramento and San foxes and a remnant goose population. Joaquin valleys manage their lands to So serious was the plight of the subspe- provide wintering habitat for ...
- Centre for Biodiversity Theory and Modelling
- Centre for Biodiversity Theory and Modelling

... MacArthur et al. 1972). A large number of papers have examined this phenomenon (summarized by Faeth 1984, Wright 1980), and have sought to explain why in some cases aggregate densities were lower (density undercompensation) or higher (density overcompensation) on islands when compared with equivalen ...
Thrall, P. H., M. E. Hochberg, J. J. Burdon and J. D. Bever. 2007
Thrall, P. H., M. E. Hochberg, J. J. Burdon and J. D. Bever. 2007

... vice versa are limited to ‘diffuse’ effects. Rather, it is because most species interact with suites of other species that vary dynamically across geographical landscapes, that coevolutionary processes can be important in organising communities and maintaining variability within specific interaction ...
Full-Text PDF
Full-Text PDF

... more difficult for some species [48]. In other groups of butterflies, inter-patch distance can affect colonization and population persistence [49–51] and corridors can enhance movement between habitat patches [52,53]. For example, it is not uncommon for some butterfly species to regularly cross two- ...
Chapter 4. Complex Life Cycles and Marine Food Webs: Migrating
Chapter 4. Complex Life Cycles and Marine Food Webs: Migrating

... defined by storage of carbon, whereas in marine food webs it’s determined by high turnover rates and production of carbon (fig 4.1A). The ‘challenge’ then for a consumer in marine system is to capture dilute sources of energy that are mostly produced by small-sized plankton. Cohen (1994) highlighted ...
New Zealand Journal of Forestry Science
New Zealand Journal of Forestry Science

... We submit that the long-held notion that eradication can only occur by eliminating all individuals within a population (Dahlsten et al., 1989; Knipling, 1979) is false. There is ample evidence that most insect species exhibit both stochastic dynamics and Allee effects at low densities, and that thes ...
The consequences of scale: assessing the distribution of benthic
The consequences of scale: assessing the distribution of benthic

... Evidence suggests that patterns of benthic community structure are functionally linked to estuarine processes and physical characteristics of the benthos. To assess these linkages for coarse-sediment shorelines, we used a spatially nested sampling design to quantify patterns of distribution and abun ...
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Occupancy–abundance relationship

In ecology, the occupancy–abundance (O–A) relationship is the relationship between the abundance of species and the size of their ranges within a region. This relationship is perhaps one of the most well-documented relationships in macroecology, and applies both intra- and interspecifically (within and among species). In most cases, the O–A relationship is a positive relationship. Although an O–A relationship would be expected, given that a species colonizing a region must pass through the origin (zero abundance, zero occupancy) and could reach some theoretical maximum abundance and distribution (that is, occupancy and abundance can be expected to co-vary), the relationship described here is somewhat more substantial, in that observed changes in range are associated with greater-than-proportional changes in abundance. Although this relationship appears to be pervasive (e.g. Gaston 1996 and references therein), and has important implications for the conservation of endangered species, the mechanism(s) underlying it remain poorly understood
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